Recently I've emerged 3.8.13 kernel and now my wireless connection works only a few seconds. After that although wpa_gui shows that I'm still connected in fact I cannot reach any webpage or even ping anywhere. To connect again for another ~5 sec I need to restart wpa_supplicant.

On the same machine with the same network configuration (/etc/conf.d/net, dhcpcd.conf, wpa, and so forth) I still have old kernel 3.5.7 where I do not experience such issue so most probably this is the problem of a new kernel or my misconfiguration of it.
In fact not very much have changed in ".config" since 3.5.7 from my side, here is the diff:

A workaround may help, although it's not a fix at all; instead of restarting wpa_supplicant, $ wpa_cli scan or wpa_cli scan_result from the commandline reconnects my wifi dongle. (I don't remember exactly which does the job. Maybe any of two does.)

My 3.8.13-gentoo kernel is working all right with an Intel wireless-N adapter (mPCIe)... I also used a 3.8.13-gentoo kernel with a b43 Broadcom wifi that appears to work fine too (mini PCI). Both are using networkmanager/Gnome._________________Intel Core i7 2700K@ 4.1GHz/HD3000 graphics/8GB DDR3/180GB SSDWhat am I supposed watching?

Looking at the dmesg it seems to delay loading the firmware, try to build the firmware into the kernel.

In "Generic Driver Options" you can list them in "External firmware blobs to build into the kernel binary" and also point where to find them "Firmware blobs root directory" (probably /lib/firmware), you probably want to read the other options there as well. I don't have an idea how the firmware name is called though, so that's something that still needs to be figured out; you can find the firmware files in /lib/firmware, look for b43*.fw files, they could be in a sub directory.

thanks, but the firmware's delay is not the problem for sure, because after a few minutes and after being working right, if I look for networks around in the Kde4 network menu they have all gone except the one I'm connected to.

So it looks like the Networkmaneger or the network menu cannot look for networks, but for sure is something kernel related, because it only happens with this last kernel, and when I do iwlist wlan0 scan (twice or more times, not only one time) I can see all networks around.

So I'm going to check the kernels options again. And try what you said, but I do not think is the firmware.

which, as far as I googled about, is related to bug in firmware (I'm using sys-kernel/linux-firmware for this module).

Anyway 3.10.1 + bcma + linux-firmware is the best configuration for me, at least it works on every network which I have tested._________________Vanitas vanitatum et omnia vanitas.
Libera temet ex inferis.